矿床三维地质建模及储量估算——以丰村铅锌矿径口矿段为例

钦杭成矿带是我国最重要的成矿带之一,丰村铅锌矿位于钦杭成矿带南段庞西垌地区,是区内典型的沉积热液改造型矿床。依据现代成矿预测理论,结合已有的地形地质图、勘探线剖面图、钻孔数据等资料,运用三维地质建模技术建立了丰村铅锌矿径口矿段的地表模型、断裂模型、地层实体模型、矿体模型。在此基础上分别应用地质块段法和块体模型统计法进行了矿体的资源储量估算,并将两种估算结果进行了对比分析。结果表明,块体模型统计法比地质块段法应用范围更广,效果更精准,可以清晰表达矿体品位值变化特征,进而加深对矿体、矿床的空间分布规律的认识。同时,利用多元信息进行三维地质建模,可靠性高,可视化效果好。将传统的二维地质拓展到三维空间进行定位与定量化,有助于分析矿区地质构造特点与矿床成因,是现代寻找矿床的一种有效手段。

Three-dimensional geological modeling of deposits and reserve estimation: A case study on the Jingkou ore block of Fengcun Pb-Zn deposit

The Qinzhou-Hangzhou metallogenic belt is one of the most important metallogenic belts in China. The Fengcun Pb-Zn deposit is a typical reworked sedimentary-hosted hydrothermal deposit in the Pangxidong area of this belt. Based on the modern metallogenic prediction theory, in combination with geological data and drilling data available, this work built three-dimensional geological models of the Jingkou ore block of the Fengcun Pb-Zn deposit, which include a surface model, fault model, stratigraphic model and ore body model. Then we made a visual reserve estimation using the geological ore block method and block model statistics method. The estimates proved that the block model statistics method applicable to a larger scope and can obtain better results than the geological ore block method. It can show clearly the variation features of ore grade values and further understanding of spatial distribution regularity. Meanwhile, 3D geological modeling using multivariate information has several advantages such as high reliability, convenience, better visualization and accuracy. We can use the three-dimensional modeling method to analyze the geological structure of the mining area and ore genesis better. This 3D geological technology is a valid tool to search for deposits .